Sitka glad to hear you're still riding at 80!!! As one of the early Rad Riders since 2017 I must tell you that unfortunately the Rad Rover is not a powerful off road hill climber, the hub drive motor cannot compete with mid-drives on the hills. That said I have taken my Rad to some high places which required lots of pedal assist from me with eventually using the "walk assist" function. I'll offer up my best advice to reach the summit and not fry the Bafang rear hub motor (easily done if overheated).
1.Always use the lowest gear! Take your time and enjoy the experience.
2.Any pedal assist from YOU is beneficial and almost mandatory, using throttle alone will overheat on steep hills.
3.When you do use throttle, watch your display, if you are exceeding 500 watts under full load and bogging down, the internal hub is heating up and bye bye motor.
4.When it gets real steep, get off and use the walk function.
5.What goes up must come down. Steep downhills on the way back can literally be your downfall, lower seat and make sure you periodically adjust your breaks (very easy to do with the mechanical, its just a turn of the allen wrench.)